<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  
  <style>
    .top-bar {
      display: flex;
      flex-direction: row;
      align-items: center;
      height: 45px;
      width: 375px;
      background-color: black;
      /* 关键 */
      overflow: hidden;
      transition: all .5s ease-out;
    }
    .delete {
      display: flex;
      flex-direction: row;
      justify-content: center;
      align-items: center;
      height: 100%;
      width: 30px;
      cursor: pointer;
    }
    .delete img {
      height: 10px;
      width: 10px;
    }
    .logo {
      height: 30px;
      width: 30px;
      margin-left:3px;
      margin-right: 30px;
      cursor: pointer;
    }
    span {
      color: white;
      font-size: 14px;
      flex: 1;

      white-space: nowrap;
      overflow: hidden;
      text-overflow: ellipsis;
    }
    .btn {
      width: 94px;
      height: 100%;
      line-height: 45px;
      text-align: center;
      font-size: 14px;
      color: #fff;
      background-color: #F63515;
    }
  </style>
</head>
<body>
  
  <div class="top-bar">
    <div class="delete">
      <img src="./img/delete.png" alt="">
    </div>
    <img class="logo" src="./img/logo.png" alt="">
    <span>打开京东App,购物更轻松</span>
    <div class="btn">立即打开</div>
  </div>

  <script>
    // 1.获取元素
    var topBar = document.querySelector(".top-bar")
    var deleteEl = topBar.querySelector(".delete")

    // 2.监听delete的点击
    deleteEl.onclick = function() {
      topBar.style.height = 0
      // setTimeout(function() {
      //   topBar.remove()
      // }, 300)
    }

    // 3.监听过渡动画结束
    topBar.ontransitionend = function() {
      topBar.remove()
    }

  </script>

</body>
</html>